Computational Thinking/Transcript
Transcript Text reads: The Mysteries of Life with Tim and Moby. Nat stands outside her school with Moby. They have just completed a fire drill. NAT: Well, well, if it isn't P.S. 1001010111's new fire marshal! How'd your first drill go? Moby looks bummed. He shows Nat the stopwatch he used in the drill. It reads 13 minutes and 17 seconds. MOBY: Beep. NAT: Ooo, Principal Beepmore's gonna have your badge if you don't get that time under ten minutes. Moby starts to panic. MOBY: Beep! NAT: Okay, okay, don't get your wires crossed. I'm sure we can work together to get everyone out a little faster. MOBY: Beep! Moby has an idea. He places a giant trampoline below a window of the school. The robots are supposed to bounce from the window to safety. A small robot attempts the jump, but crashes. NAT: That's… creative, but shouldn't you be keeping students… you know, safe? We should look at the problem the same way your robo-buddies would. That way, we can come up with a solution that even the most basic bot can process. The robot who crashed returns. He has tree leaves and other garbage stuck to him. He hands Nat a letter, and she reads from it. NAT: Dear Nat and Moby, I heard the last fire drill was a total disaster. Why don't you try using computational thinking? Just a thought. From, Sooo not a "basic" bot. MOBY: Beep? NAT: Computational thinking is a set of strategies for tackling complex problems. It involves breaking down solutions into steps that a computer can follow. Programmers use it to design apps, games, and other software. An animation shows a Rubik's Cube and a computer. The computer prints instructions, which make the cube rotate. NAT: But computational thinking can be useful for anyone, applied to all kinds of problems. Like, whittling down the time it takes to complete a fire drill! An animation shows Moby's stopwatch. The time begins to decrease. MOBY: Beep? NAT: CT is generally divided into four main parts. Decomposition, or decomposing a problem, breaks it down into manageable chunks. An animation shows the Rubik's Cube. It breaks apart into smaller cubes. Then it reassembles itself. NAT: Pattern Recognition involves looking for similarities across different parts of a problem. The parts of the cube with a similar color pattern light up. NAT: Abstraction is where we boil a problem down to its simplest form. The colored squares on the cube disappear. Only an outline of the large cube remains. NAT: And Algorithm Design means making a plan—a series of steps to put your ideas into action. An animation shows a diagram. The diagram shows several steps for solving the Rubik's Cube. NAT: Not every problem will require all the stages. An animation shows four cards. Each card has an icon for a step of the computational thinking process. NAT: Sometimes just focusing on one will lead to a solution. One of the cards lights up. NAT: And you don't have to follow the stages in any set sequence. The order you follow depends on the problem you're trying to solve. The cards switch places. NAT: Computational thinking is an iterative process: one that’s designed to be used over and over again to solve a problem. You'll repeat some or all of the steps based on what you learn along the way. Each iteration should get you closer to a solution. The four computational thinking steps are applied to the Rubik's Cube. It gets closer to a solution. More steps are applied in different orders until the cube is solved. MOBY: Beep? NAT: Well, first, it's a good idea to study the data: the facts and figures related to a problem. An animation shows Nat and Moby surrounded by data. NAT: Like, how long did it take each student to leave the building? How fast were they going, and where were they coming from? Nat points out these numbers as she describes them. NAT: Collecting and analyzing data drives the whole CT process. So it's a good thing you ran all those test drills this week. We've got tons of stats for everybody in the school! Now let's take all that data and decompose it! Nat offers a flash drive containing the data to Moby. NAT: You remember? Breaking the problem up into manageable chunks? Moby stares blankly. A bee buzzes into one of his ears, and out the other. Nat sighs. NAT: Okay, let's take a step back. What are some of the parts of a fire drill? MOBY: Beep? NAT: Right, there are students! We could sort all of this data you collected by each individual: How fast they' were going, their exit times, how far they traveled... Nat plugs the flash drive into a tablet. A table showing the speed, time, distance, and floor of each student appears on the screen. NAT: But… this school has more than 1,000 students. Trying to improve each of their times individually seems kind of overwhelming. Maybe there's a bigger chunk we can focus on. The animation scrolls through the long set of data. MOBY: Beep! NAT: There's an idea: Let's divide it up by classroom! We can sort their exit times from fastest to slowest… Then see which classrooms are taking the longest to exit. Nat rearranges the table to filter by time. NAT: Check out these slowpokes! They're more than three minutes behind the next slowest classroom. The table highlights the slowest classroom. It took them 13 minutes and 17 seconds to complete the fire drill. NAT: Huh, I wonder if it's just one or two super-slow bots holding everyone up. Let's look at individual student times to see if that's what's going on. Nat rearranges the table again. NAT: Nope, it looks like everyone in here is moving at around the same pace. MOBY: Beep? NAT: Okay, it's not obvious what the issue is from the quantitative data. That's all of the information that's expressed in numbers. An animation shows the image of a line graph. NAT: It's important to collect qualitative data, too: info that's harder to measure. It can include crucial details that'll help you solve the problem. The animation shows the second image of a line graph. It fades into the image of a mountain. The line from the graph makes the outline of the mountain. NAT: Let's go to the videotape. Oh, it's the lunch room—no wonder there are so many students! And it's chock-full of qualitative problems! An animation shows video of the lunchroom. It's packed with students. NAT: Like the spilled food over there causing a 13…14…15-bot pile-up. Several bots in the lunch line slip on the spilled food. They crash into each other and land in a big pile. NAT: And look at the chaos over by the doors. A crowd of robots tries to push through the door. There are so many robots that none can pass through. NAT: Hmmm… maybe the same thing is happening in other rooms. MOBY: Beep? NAT: Yup, that's what pattern recognition is all about. If we find similarities across different parts of the problem, it can help us find a solution for the whole thing. Nat views multiple classrooms at the same time on her tablet. NAT: I think I see a pattern! Bots are crowding the doors, causing major traffic jams. If they just line up neatly instead, it'll avoid the bottlenecks! Nat circles the crowded doorways in each video. MOBY: Beep! NAT: Not so fast! We still have to write the instructions these bots need to follow. That's all algorithm design means: creating a list of steps. In coding, it's the part where you actually write out the program. An animation shows a set of instructions for solving a Rubik's Cube. NAT: The algorithm has to be clear, specific, and step-by-step, or a computer won't understand it. Exact instructions like that are helpful in solving any problem. The steps of the instructions light up. The Rubik's Cube performs the steps. The process continues until the puzzle is complete. NAT: If you've ever given someone directions somewhere, you've designed an algorithm. An animation shows the map of a town. Nat draws a line to highlight the directions from the school to the park. NAT: Same with writing a recipe: it's a series of steps, in order, that anyone can follow! Or, almost anyone. An animation shows Nat following her father's cake recipe. She adds milk and then uses a mixer to stir the batter. The mixer setting is too high. The bowl's contents spill everywhere. NAT: In this case, the steps should be pretty easy. Step 1: line up at the door. Step 2: stay in a single file as you walk to the nearest exit. An animation shows Moby hanging up instruction signs around the school. MOBY: Beep! NAT: Great: All the bots have the algorithm and know what to do. Let's drill! The fire alarm goes off. The bots complete the drill. Moby clicks his stopwatch to record the time. NAT: Well, that seemed faster to me… how'd we do? Moby holds up the stopwatch. The drill took 11 minutes and 31 seconds. Moby looks dejected. MOBY: Beep. NAT: Aw, don't give up so easy! Remember, CT is all about iteration. Let's go to the security cam and see what we can see. Nat reviews the video on her tablet. The video shows the robots lining up around the room. NAT: Hm, video gives us a lot of distracting info… Maybe it's time for abstraction: cutting out unimportant stuff to get to the essence of the problem. Each of these bots has GPS. An animation shows the GPS inside one of the robots. NAT: So instead of watching video, we can see where everyone is on a map of the school. An animation shows a blueprint of the school. Dots represent the location of each robot. The dots are in one line that winds around the school. NAT: Ah ha—with all the distraction in the video I didn't even notice these other exits. Instead of using them all equally, most bots are all crowding toward one. The exit doors on the blueprint light up. NAT: If we distribute the bots evenly across all exits, it should cut down our time. The dots change so that there is an equal group of dots at each exit. NAT: Now all we have to do is add some steps to our algorithm. We'll assign one of four colors to each bot… and label each door with one of those colors. An animation shows Moby giving colored headbands to the bots in the school. He also paints the exit doors. NAT: When the alarm rings, blue bots will line up at blue doors, red bots at red doors, and so on. An animation shows the red bots lining up at a red door. NAT: Once everyone's lined up, they'll exit into the hallways. Colored stripes on the floors will route them out of the school. All they have to do is follow their stripe! An animation shows Moby painting colored stripes on the floor. He finishes and returns to Nat covered in paint. MOBY: Beep! NAT: Thanks, Mobes! Now we just have to run another fire drill to see if it works. Moby reaches for the fire alarm. NAT: No, wait! Moby pulls the fire alarm before Nat can stop him. The robots file out of the school and trample Nat and Moby in the process. Moby clicks the stopwatch to record the time. MOBY: Beep. NAT: Nine minutes… 48 seconds… We did it! MOBY: Beep! Moby starts to celebrate his victory. NAT: Uh, I'll join you… in a little while. I'm just… I'm just gonna lie here a bit. Nat rests her head on the ground. Category:BrainPOP Transcripts Category:BrainPOP Engineering & Technology Transcripts